[10/17] r6040: fix r6040_multicast_list

[Greg KH <gregkh@suse.de>]

2.6.27-stable review patch.  If anyone has any objections, please let us know.

------------------

From: Florian Fainelli <florian@openwrt.org>

commit 3bcf8229a8c49769e48d3e0bd1e20d8e003f8106 upstream.

As reported in <https://bugzilla.kernel.org/show_bug.cgi?id=15355>, r6040_
multicast_list currently crashes. This is due a wrong maximum of multicast
entries. This patch fixes the following issues with multicast:

- number of maximum entries if off-by-one (4 instead of 3)

- the writing of the hash table index is not necessary and leads to invalid
values being written into the MCR1 register, so the MAC is simply put in a non
coherent state

- when we exceed the maximum number of mutlticast address, writing the
broadcast address should be done in registers MID_1{L,M,H} instead of
MID_O{L,M,H}, otherwise we would loose the adapter's MAC address

[bwh: Adjust for 2.6.32; should also apply to 2.6.27]

Signed-off-by: Florian Fainelli <florian@openwrt.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Cc: Ben Hutchings <ben@decadent.org.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

---
 drivers/net/r6040.c |   11 ++++-------
 1 file changed, 4 insertions(+), 7 deletions(-)

--- a/drivers/net/r6040.c
+++ b/drivers/net/r6040.c
@@ -135,7 +135,7 @@
 #define RX_DESC_SIZE	(RX_DCNT * sizeof(struct r6040_descriptor))
 #define TX_DESC_SIZE	(TX_DCNT * sizeof(struct r6040_descriptor))
 #define MBCR_DEFAULT	0x012A	/* MAC Bus Control Register */
-#define MCAST_MAX	4	/* Max number multicast addresses to filter */
+#define MCAST_MAX	3	/* Max number multicast addresses to filter */
 
 /* Descriptor status */
 #define DSC_OWNER_MAC	0x8000	/* MAC is the owner of this descriptor */
@@ -969,9 +969,6 @@ static void r6040_multicast_list(struct
 			crc >>= 26;
 			hash_table[crc >> 4] |= 1 << (15 - (crc & 0xf));
 		}
-		/* Write the index of the hash table */
-		for (i = 0; i < 4; i++)
-			iowrite16(hash_table[i] << 14, ioaddr + MCR1);
 		/* Fill the MAC hash tables with their values */
 		iowrite16(hash_table[0], ioaddr + MAR0);
 		iowrite16(hash_table[1], ioaddr + MAR1);
@@ -987,9 +984,9 @@ static void r6040_multicast_list(struct
 		dmi = dmi->next;
 	}
 	for (i = dev->mc_count; i < MCAST_MAX; i++) {
-		iowrite16(0xffff, ioaddr + MID_0L + 8*i);
-		iowrite16(0xffff, ioaddr + MID_0M + 8*i);
-		iowrite16(0xffff, ioaddr + MID_0H + 8*i);
+		iowrite16(0xffff, ioaddr + MID_1L + 8*i);
+		iowrite16(0xffff, ioaddr + MID_1M + 8*i);
+		iowrite16(0xffff, ioaddr + MID_1H + 8*i);
 	}
 }